Musar su Genesi 27:28

ויהי לי שור וחמור . This statement has to be understood at face value when it was addressed to Esau in line with Rashi's explanation that, whereas in Isaac's blessing Jacob was promised "dew from the heavens and the fat parts of the earth," i.e. success as a farmer, he had in fact only acquired herds. Esau had no reason to be jealous, since that part of Isaac's blessing had not been fulfilled. The same words put in the mouth of Jacob's spiritual emissaries convey a different meaning, however. These words allude to a number of merits Jacob had acquired and that would accrue to him in the future. They correspond very much to Bereshit Rabbah 75,6 which explains that the word שור refers to the כהן משוח מלחמה, the priest who accompanied the troops into battle (Deut. 20,2). The Midrash bases this on Moses' blessing to the tribe of Joseph in Deut. 33, 17: בכור שורו הדר לו, "His firstling bullock, majesty is his." The word חמור is understood as a reference to the Messiah who traditionally is perceived as riding on a donkey, based on Zachariah 9, 9: עני ורוכב על החמור. The צאן, flock, that Jacob also mentions refers to the people of Israel who are repeatedly called צאני"My flock," by G–d in Ezekiel 34. The words עבד ושפחה also refer to Israel as the latter are alluded to in that manner in Psalms 123, 2.

In order to answer all these problems allow me two introductory remarks: 1) The blessings are capable of two interpretations. One interpretation, i.e. the פשט, views all the blessings in terms of material benefits in this world. G–d will grant sufficient dew in the summer to enable the fruit to grow in the fields. He will allow Jacob to feed on the fat part of the earth etc. 2) The other interpretation of the blessings sees in their wording allusions to the real blessings of the Torah which pertain to a "higher" world, i.e. the world in which blessings are of enduring value. The Midrash describes טל השמים as an allusion to the written Torah, משמני הארץ as a reference to Mishnah; דגן alludes to Talmud, whereas תירוש alludes to the Aggadic material in the Talmud. According to this interpretation both the words השמים and הארץ refer to their respective counterparts in the Celestial Regions. It appears that Bereshit Rabbah 67,2 refers to this when quoting Isaac as telling Esau ואוכל מכל, "I ate from it all" (Genesis 27,33). We find there that Rabbi Yehudah understands the word as meaning "all that has been created during the six days of creation," whereas Rabbi Nechemiah understands the expression as meaning "all that is stored up for future consumption in the World to Come." Both these Rabbis have correctly interpreted the blessings, each one emphasizing a different aspect. Even though the delicacies served Isaac were certainly made of foods available here on earth, of items created during the six days of Creation, they exuded a taste of something super-natural, something of the World to Come.